If you are a user before 9.2, you must specify the XY domain when generating a number class or number set. Otherwise, an error is returned that exceeds the range, but you do not need to manually specify the range in 9.2.
Whats_new_in_arcgis92.pdf page 18th (Geodatabase & ArcSDE-easier to create data) When you generate data by yourself, the new high-precision data storage method has been adopted in 9.2, and you do not need to manually specify XY domain. When you create a single number class or number set in 9.2, the software automatically calculates the appropriate XY domain for your own coordinate system. Of course, during the wizard generation process, minx, miny, Maxx, and Maxy involved in the range are no longer editable, or even invisible to you. The appropriate precision value is also calculated in this process, but you can manually specify this value.
